Bluetail Trunkfish

The Bluetail Trunkfish is a compact and colorful member of the boxfish family, easily recognized by its vivid blue caudal fin and tail region that contrasts beautifully with its olive to yellowish-brown body. Males are particularly striking, displaying bright blue tones on the rear of their rigid carapace and tail, along with subtle yellow and blue patterning across the body. Females and juveniles tend to be more muted, with a brownish-olive base color and faint spotting.

Reaching approximately 6 inches in length, this species is one of the smaller boxfish available in the marine aquarium trade. It requires a minimum tank of 75 gallons with plenty of open swimming space and stable rockwork for shelter. In the wild, the Bluetail Trunkfish inhabits coral reefs and rocky lagoons throughout the Indo-Pacific and Red Sea, where it forages on small invertebrates, algae, sponges, and tunicates.

Like all members of the Ostraciidae family, this species can release ostracitoxin from its skin when severely stressed or dying, which can be lethal to other tank inhabitants. This makes it essential to maintain a stress-free environment with calm, non-aggressive tankmates. Despite this risk, the Bluetail Trunkfish is a rewarding aquarium specimen with an engaging personality and striking coloration. It is not considered reef-safe as it will readily feed on small invertebrates and may nip at coral polyps.